<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Symbol内置属性</title>
</head>
<body>
<script>
    // class Person{
    //     static [Symbol.hasInstance](){
    //         console.log("aabbcc");
    //     }
    // }
    //
    // let o = {};
    // console.log(o instanceof Person);

    const arr = [1,2,3];
    const arr2 = [4,5,6];
    arr2[Symbol.isConcatSpreadable] = false;
    console.log(arr.concat(arr2));
</script>
</body>
</html>